Context:

Recently, researchers have isolated and described India’s first cultures of indigenous methanotrophs (Methane-utilizing) bacteria.

Discovery of Unique Methanotrophs:

• Researchers from the Maharashtra Association for the Cultivation of Science, (MACS) Agharkar Research Institute have made a significant breakthrough by isolating and describing India’s first indigenous methanotroph cultures from rice fields and wetlands in Western India. 
• Methanotrophs, or methane-oxidizing bacteria, consume methane to build biomass, using oxygen and releasing CO2 and H₂O.
• Researchers have identified a new genus and species of methanotroph, Methylocumulus oryzae, notable for its cucumber-like shape and ability to oxidize methane
• This methanotroph, dubbed ‘methane-eating cucumbers’, is phylogenetically unique and has not been reported or cultured elsewhere in the world.

Methane (CH₄)

• It is primarily composed of natural gas, is an odorless, colorless, and tasteless gas that is lighter than air.
• Burns with a blue flame in complete combustion, yielding carbon dioxide (CO2) and water (H2O) in the presence of oxygen.
• Methane is the second most abundant anthropogenic Greenhouse gas (GHG) after carbon dioxide (CO2), accounting for about 16 percent of global emissions. 
• Methane is more than 26 times as potent as carbon dioxide at trapping heat in the atmosphere.
• The International Energy Agency’s Global Methane Tracker 2024 indicates that methane emissions from fuel totaled close to 120 million tonnes (MT).
• The top three GHG emitters — China, the United States and India — contribute 42.6% total emissions, while the bottom 100 countries only account for only 2.9%.
• The United States is the largest emitter of methane from oil and gas operations, closely followed by Russia. While China is the highest emitter of methane in the coal sector.
• Norway and the Netherlands have the lowest emissions intensities. 

Unique Characteristics and Applications

• Methylocucumis oryzae stands out due to its unusually large size (3-6 µm) compared to other bacteria and its strict mesophilic nature, thriving only up to 37ºC.
• Notably, this methanotroph has shown potential in promoting rice plant growth, enhancing early flowering, and increasing grain yield.
• Methylocucumis oryzae is abundant in natural environments such as wetlands and rice fields. Here, it plays a significant role in methane mitigation.

Challenges and Future Prospects

• Despite its promising features, Methylocucumis oryzae faces challenges like slow growth, which hampers large-scale cultivation. 
• However, its abundance in natural habitats and its unique characteristics make it a valuable candidate for further research and applications in climate change mitigation and biotechnology. 
• Continued advancements in cultural conditions could unlock its full potential in combating greenhouse gases and supporting agricultural productivity.